Premium
Peripheral moving‐table contrast‐enhanced magnetic resonance angiography (CE‐MRA) using a prototype 18‐channel peripheral vascular coil and scanning parameters optimized to the patient's individual hemodynamics
Author(s) -
Potthast Silke,
Wilson Gregory J.,
Wang Maisie S.,
Maki Jeffrey H.
Publication year - 2009
Publication title -
journal of magnetic resonance imaging
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.563
H-Index - 160
eISSN - 1522-2586
pISSN - 1053-1807
DOI - 10.1002/jmri.21540
Subject(s) - flip angle , magnetic resonance angiography , peripheral , magnetic resonance imaging , medicine , scanner , angiography , electromagnetic coil , radiology , biomedical engineering , nuclear medicine , computer science , physics , quantum mechanics , artificial intelligence
Purpose To demonstrate that with a priori determination of individual patient hemodynamics, peripheral contrast‐enhanced magnetic resonance angiography (pCE‐MRA) can be customized to maximize signal‐to noise ratio (SNR) and avoid venous enhancement. Materials and Methods Using a 1.5T MRI scanner and prototype 18‐channel peripheral vascular (PV) coil designed for highly accelerated parallel imaging, geometry (g)‐factor maps were determined. SNR‐maximized protocols considering the two‐dimensional sensitivity encoding (2D SENSE) factor, TE, TR, bandwidth (BW), and flip angle (FA) were precalculated and stored. For each exam, a small aortic timing bolus was performed, followed by dynamic three‐dimensional (3D)‐MRA of the calf. Using this information, the aorta to pedal artery and calf arteriovenous transit times were measured. This enabled estimation of the maximum upper and middle station acquisition duration to allow lower station acquisition to begin prior to venous arrival. The appropriately succinct SNR‐optimized protocol for each station was selected and moving‐table pCE‐MRA was performed using thigh venous compression and high‐relaxivity contrast material. Results The protocol was successfully applied in 15 patients and all imaging demonstrated good SNR without diagnosis‐hindering venous enhancement. Conclusion By knowing each patient's venous enhancement kinetics, scan parameters can be optimized to utilize maximum possible acquisition time. Some time is added for the timing scans, but in return time‐resolved calf CE‐MRA, maximized SNR, and decreased risk of venous enhancement are gained. J. Magn. Reson. Imaging 2009;29:1106–1115. © 2009 Wiley‐Liss, Inc.